For many yeart the packaging of electronic circuitry has been limited by two considerations: 1 the ease of interconnecting the electronic circuitry, and 2 the need to allow for sufficient heat dissipation in the packaged circuitry for long life operation. However, as the switching speed of electronic circuits became faster and faster, an additional constraing on circuit packaging was the need to reduce signal propagation delay times. Obviously, if a pulse has a rise time in the nanosecond range and it takes the pulse micro seconds to reach its intended destination, the pulse has not been effectively utilized. Fortunately, at about the same time that this factor became significant, integrated circuitry was introduced which greatly reduced the dimesions of electronic circuits. Thereafter, for much integrated circuit packaging the significant constraint was space necessary for heat dissipation and signal propagation delays were not significant.
However, with the advent of superconductive circuitry and Josephson tunneling devices, switching times have been decreased by a number of orders of magnitude. It had been reported that Josephson tunneling junctions can be switched in times in the order of 10.sup..sup.-11 seconds. To effectively utilize such switching speed it becomes necessary to provide a circuit package or module, in which the signal propagation delays are not so long as to negate the tremendous advantages gained by such rapid switching. However, it is not merely a question of arranging a plurality of circuits or chips for reduced signal propagation delay times; but the need is to do so practically. The practical aspect of such a package requires that it be possible to make interconnections to circuits or chips of extremely small dimensions. The prior art teaches extensive planar arrays of integrated circuit chips and the means necessary to interconnect the same. However, these large planar arrays of integrated circuit chips are not suitable for superconductive circuitry, especially such circuitry employing Josephson tunneling devices. As has been referred to above, the extreme speed of the Josephson tunneling devices would not be effectively utilized in employing the prior art packaging techniques. The signal delay propagation times would be so long as to negate the effectiveness of the high switching speed of which these devices are capable.